A. Field of the Invention
The present invention relates to equipment and apparatus used for controlling properties of air in structures occupied by people or animals. More particularly, the invention relates to an air conditioning apparatus for controlling the temperature and humidity of air within enclosed spaces such as interior rooms of a building or other structure.
B. Description of Background Art
Heating, ventilating and air conditioning (HVAC) systems for controlling the interior environment of buildings and other structures occupied by humans utilize a variety of well known equipment and apparatus for conditioning air within the structure to comfortable temperatures and humidity levels and to remove air-borne pollutants including particulates such as dust.
Heating the interior space of a building is a relatively straight forward task, since latent energy sources such as electricity, gas, oil, or coal are readily input into a heater or furnace within the building, or by conveying working fluid heated by solar panels or the earth into the building to raise the temperature to a desired value. Cooling a building is more problematic, since that task requires expenditure of energy to exhaust heat from the building and also generally requires relatively large heat exhaust ducts and heat exchangers to dump the removed heat energy into an environment exterior to the building. Thus, room air conditioners are typically installed in a window opening, with the condenser portion of closed-cycles, pressurized refrigerant systems being located exterior to the room, where heat is exhausted to the atmosphere by the condenser, primarily by forced convection and secondarily by passive convection and black-body radiation.
In certain situations, it is desired to provide means for temporarily cooling a room. In response to this application, a variety of xe2x80x9cportable air conditionersxe2x80x9d have been made available. However, most of these utilize a flexible air duct for conducting warm air to a region exterior to the room. Such ducts are typically coupled to a window opening to the outside of the building. Aside from the inconvenience of having to couple a flexible air duct temporarily to a window opening, such openings are unavailable in interior rooms of a structure. The present invention was conceived of to provide a convenient means for cooling and conditioning air within an isolated space such as the interior of an inner room within a building or other structure.
An object of the present invention is to provide an air conditioning apparatus for cooling air within isolated spaces.
Another object of the invention is to provide an air conditioning apparatus for cooling and/or dehumidifying air within an isolated space.
Another object of the invention is to provide an air conditioning apparatus for selectably cooling, humidifying, dehumidifying, and filtering air within an interior space of a structure.
Various other objects and advantages of the present invention, and its most novel features, will become apparent to those skilled in the art by perusing the accompanying specification, drawings and claims.
It is to be understood that although the invention disclosed herein is fully capable of achieving the objects and providing the advantages described, the characteristics of the invention described herein are merely illustrative of the preferred embodiments. Accordingly, I do not intend that the scope of my exclusive rights and privileges in the invention be limited to details of the embodiments described. I do intend that equivalents, adaptations and modifications of the invention reasonably inferable from the description contained herein be included within the scope of the invention as defined by the appended claims.
Briefly stated, the present invention comprehends an air conditioning apparatus for isolated interior spaces, such as a space within an inner or windowless room of a structure such as a building. With all access openings, such as doorways to an interior spaced closed, the space may be referred to as xe2x80x9cquasi hermetically isolated.xe2x80x9d An air conditioning apparatus for isolated spaces according to the present invention includes a box-like cooling enclosure which includes means for drawing air from the interior space of a room through the box, means for filtering particulates from the air, means for cooling the air, means for selectably humidifying or dehumidifying the air, and means for expelling conditioned air into the interior space of the room.
A preferred embodiment of the present invention includes at least one evaporative cooler assembly which comprises a plurality of spray nozzles that are supplied with water under pressure, the nozzles spraying water into a stream of air flowing against the direction of the spray streams. In a preferred embodiment, water is supplied to the spray nozzles from a source such as a kitchen faucet, and discharged to a location exterior to a space air-conditioned by the apparatus, such as a sewer drain. The air conditioning apparatus according to the present invention also preferalby includes at least one closed-cycle refrigeration assembly which uses a pressurized refrigerant such as Freon.
According to the invention, the closed-cycle refrigeration assembly includes a compressor having a discharge line which is input to a refrigerant-to-water heat exchanger or condenser that includes a serpentinely coiled pressurized refrigerant tube which is in thermally conductive contact with water which flows through a housing containing the coil. In a preferred embodiment, cooling water for the water heat exchanger is supplied from a source such as a kitchen faucet, and is discharged to a location exterior to a space air conditioned by the apparatus, such as a sewer drain.
Pressurized liquid refrigerant cooled by the refrigerant-to-water heat exchanger is preferably further cooled by a pressurized liquid refrigerant-to-suction line heat exchanger. Cooled, pressurized liquid refrigerant is conveyed by a capillary tube to the inlet port of a closed, pressurized evaporator unit within the cooling box. Serpentine cooling coils within the evaporator unit have a larger flow cross section than the pressurized liquid refrigerant capillary tube, whereby liquid refrigerant in the pressurized capillary tube expands into the evaporator coils and produces a cooling effect, thus cooling air which is drawn through the coils by a fan. Refrigerant is drawn from an outlet port of the evaporator unit by a suction line which is coupled to a suction inlet port of the compressor, and as stated above, which is preferably thermally coupled to the capillary refrigerant inlet line by a refrigerant-to-suction line heat exchanger.
A preferred embodiment of an air conditioning apparatus according to the present invention includes a perforated spray eliminator plate disposed transversely to the air flow direction in the cooling box, and upstream of the conditioned air exhaust port. The spray eliminator plate is effective in removing a portion of water droplets which may be entrained in the cooled air stream. Optionally, one or more additional spray eliminator plates may be included in the cooling box to remove additional entrained water droplets, and to control air flow. By operating the spray evaporative cooler assembly when the ambient air is sufficiently dry, evaporative cooling and humidification are accomplished. If additional cooling, and/or dehumidification is desired, one or more of the pressurized refrigerant compressors may be turned on, thus further cooling and dehumidifying exhausted air. Importantly, heat removed from air flowing through the cooling box is transferred to a water stream which is discharged into an external location such as a sewer drain, thus enabling the apparatus according to the present invention to effectively cool an isolated interior space of a building or other structure which may be isolated or even quasi-hermetically sealed.